Heavy fluid writing pen



Nov. 22, 1966 J. M. MARTIN HEAVY FLUID WRITING PEN Filed April 22, 1966 INVENTOR Jack M. Marl-in A'H'orney United States Patent Ofifice 3,286,695 Patented Nov. 22, 1966 3,286,695 HEAVY FLUID WRITING PEN Jack M. Martin, 10014 Mansel Ave., Inglewood, Calif. Filed Apr. 22, 1966, Ser. No. 544,609 Claims. (Cl. 120-44) This is a continuation-in-part of my application Serial Number 444,639, filed April 1, 1965, now abandoned.

This invention relates to a new construction of linedrawing instrument or stylographic pen of the type wherein Writing fluid is supplied to the work surface from the mouth of a barrel rather than from a pointed stylus; such pens in the past had a pressure retractable pin within the barrel so as to retard the out-flowing fluid, as well as to clear the aperture when it became clogged. Such pens, like ordinary writing pens, were designed for use with relatively free-flowing ink, for example, on the order of 18 to 25 centipoises. Such ink is in effect adsorbed on writing paper; in contrast it will not write on glass. My pen however is adapted to employ viscous fluids, on the order of 150 to 500 centipoises, which are quick drying like a lacquer, and adhere to the work surface, such as ceramic, glass, metal, etc. A particular utilization of such marking instrument and fluid, is in the formation of printed circuit diagrams on copper plate. Thus a new circuit can be drawn by hand by the experimenter, on a thin copper surface on which it will be dried in a few minutes and can then be placed immediately in the etching solution.

The problem in pen construction however is not to slow a free-flowing ink as it approaches the run off point, but rather how to urge a sluggish and quick drying material to keep going, even at a slow speed, to the contact with the work surface. For this purpose, the invention provides a dome-shaped contact surface from which the marking fluid is wiped off onto the work piece by movement of the pen therealong, the contact surface forming the projecting (non-rolling) end of a fluted rod disposed in the pen barrel and along which fluted channels the fluid is urged outward by the operational vibration of the closely fitting rod within the barrel. A longitudinal, operating spindle is employed, of which the fluted rod forms the distal end, so that the rod may be retracted to clean the aperture, and also to close and open an upper valve member which serves to seal (when not in use) the fluid reservoir through which the spindle is threadedly disposed. The pen can thus be kept, when not in use, in the same upright position as when writing, and fluid will not appreciably escape even in long-time storage; but upon the valve being open to resume writing-use, the outlet aperture will simultaneously be cleared of hardened fluid.

There is also provided a stand for holding the pen between periods of use, such stand being especially formed to support the distinctive shape of the pen body and dispose the projecting c-ontact-end spaced free of the inner wall thereof and thus protected as well against buifeting by any external object.

Other objects and advantages will become apparent from the following description of a specific embodiment of the invention as particularly illustrated in the drawings whereinp FIGURE 1 is a perspective view of my pen and supporting stand, with a portion of the wall of the stand broken away.

FIGURE 2 is a vertical axial sectional view of the pen itself, with some portions shown in lateral elevation.

FIGURE 3 is a transverse sectional view taken along the line 3-3 of FIGURE 2.

FIGURE 4 is a transverse sectional view taken along the line 4-4 of FIGURE 2.

FIGURE 5 is an enlarged view of the fluid outlet end of the pen, as indicated generally by the arrowed circle of FIGURE 2.

FIGURE 6 is a bottom view of FIGURE 5 along the line 66.

The composite writing instrument or pen 11 is formed with a normally upright, tubular body 10, having an upper, outwardly flared, open mouth segment 12, successive cylindrical 8 and conic 9 segments therebeneath, followed by an internally threaded length 13 which serves as a reservoir for writing fluid. Beneath the threaded portion is an axially restricted, unthreaded length 19 which may externally receive a press-fit collar C for semi-permanent attachment to a handle or pen holder H by means of an intermediate shank 25 and permanently-bowed stub shaft S. Distal to the length 19, the body 10 is formed with a tubular length 18 of still less circumference which is characterized by a smooth cylindrical bore B along which the writing fluid moves to an annular outlet or aperture 26.

Axially disposed within the tubular body 10, and having a greater overall length so as to project from both ends thereof, is a spindle structure 20, intermediately having an externally threaded boss 14 which is located within the threaded reservoir 13 of the body 10 in functional engagement therewith. The threaded portion 14 is longitudinally slotted or apertured at 28 so that the reservoir fluid above and below the same will remain in open communication. Accordingly, by small manual manipulation of the spindle 20, effected by turning the protruding head or knob 21, the spindle can be raised or lowered within the body 10 without thereby causing the lower delivery column of fluid to either spurt or suck back.

However, the spindle 20 carries a radially-directed disk or closure-valve V, having a beveled or conically tapered, contact edge 7 which seats snugly against the complementary face D of the conic segment 9 when the spindle is screwed down so as to engage the disk V and seat D. This prevents fluid from slowly dripping or escaping from the outlet 26 when the instrument is not in use (and especially when it is stored in upright position with a full reservoir). In order to permit such flow during'use, the spindle 20 and valve V are of course positioned in an elevated or open position.

The distal or lower end of the spindle 20 is formed as a cylindrical, spirally-fluted rod 17 which is supportingly received, lengthwise or axially movable, within the tubular length 18, and terminating in a somewhat arcuate or dome-shaped end 27 normally projecting therefrom. The portion of the spindle 20 disposed within the unthreaded tube length 19, has a peripheral pair of longitudinallydirected ribs 16, in sliding contact with the inner face thereof and defining lengthwise fluid passages 29 (FIG- URE 4) therebetween. The viscous fluids used with the present instrument, such as lacquers employed to draw printed-circuit diagrams, do not flow readily, so that essentially the fluid is wiped off of the dome-end 27 onto the work surface, often through the application of some pressure by the user. Consequently it is desirable to supply a fairly stable or bracing support adjacent the working end of the instrument, as by the slide-ribs 16, in addition to the lateral support for the fluted rod 17 by the embracing tube length 18. At the same time, a small resiliency of the rod 17 within the tube 18 during use, appears to urge the heavy fluid down the longitudinal fluting channels 30.

In normal usage, the amount of projection P of the curved end 27 may be on the order of, say, 0.007 inch; a further projection of perhaps 0.002 or 0.003 inch will then seat the valve V so as to cut off further flow. However, since the contact end 27 is always protruding and the more so when not in use, a protective stand is provided (FIGURE 1) for holding the instrument, both intermittently while on a job as well as for longer storage. That is, the holder can be used at will whether the valve V is open or closed, so its function is to support the instrument upright in a re'ady-for-use posture while shielding the contact end 27 against accidental buffeting.

The two-piece holder of FIGURE 1 consists essentially of an inverted thimble T and a coil-shape footing member F. The thimble can be readily formed of a short length of tube stock having a minimum diameter of the lowermost segment 31; successively larger bands 32, 33 including an outwardly flared lip 34 are positioned thereabove with an open-top, lengthwise or axially-directed, slot 35 formed therealong. The slot 35 loosely receives the shaft S of the handle assembly, while the tubular body is slidably received within the loosely embracing band 33. The lower lengths of the pen body 10 and the projecting contact-end 27 are thus suspended within the band 32, laterally spaced from its inner face.

The lowermost segment 31 of the thimble is press-fit about an upstanding, central stud 36 of a generally horizontally-disposed, single split-ring of a coil 37 which may be of tube or bar stock and thus sits easily on any flat surface such as a table or work bench.

It will be apparent that the width of a line drawn by the instrument will be that of the diameter (or less) of the rod 17, rather than the larger diameter of the tube 18 as in prior pens. Also, in such prior pens which had a loose-fitting pin disposed in the outlet barrel an ink of aqueous consistency thus flowed down the annular clearance; my fluted rod 17 has only enough clearance to allow its occasional axial displacement, and thus it is afforded continued lateral support from the tube 18 along its terminal length. For example, I use a fluted rod of 0.013 in. diameter in a 0.014 in. tube; and with this size, I prefer a marking fluid of 150250 cps. With a 0.017 in. rod in an 0.018 in. tube, I use fluid of 200-350 cps. With a 0.023 in. rod in an 0.024 in. tube, I use fluid of 300500 cps. In each case, each of the pair of fluting channels is about of the rod diameter; the center web is about 60%. Typically the 150 cps. fluid will lay down a thin line of in. width, with the designated rod. All these fluids or surface coatings (e.g. lacquers, enamels, latex paints) might be termed of brushable consistency.

A particular advantage is gained from attachment of the shank S or collar C to the intermediate cylindrical length 19 along the same horizontal level at which the support ribs 16 are internally located. Such area thus provides a fulcrum for the length of rod 17 which is dependent therefrom, in that vibration of the fluted rod within the tube 18, as a result of moving the contact end 27 across a work surface, urges the sluggish fluid down the fluting channels 30.

It will be clear to those skilled in the art that various changes of construction and operation may be made within the present inventive concept, having in mind the substitution of functional equivalents within the ability of one skilled in the art, and therefor this disclosure is not to be limited by the precise details shown in the drawings and particularly described in the specification by way of example, but it is my intention to hereafter claim the invention broadly aside from the limitations inherent in the prior art.

I claim:

1. A heavy-fluid writing pen of the character described, comprising:

a tubular body forming a fluid reservoir, and a dependent outlet tube disposed for gravitational passage of viscous writing-fluid from the reservoir lengthwise through said tube to an outlet mouth, said body above the outlet tube being formed with a length characterized by a smooth bore and greater internal diameter than the outlet tube,

a generally cylindrical rod disposed axially movable Within said body and having positioning means for selectively locating it therealong with a distal length of the rod closely embraced by said outlet tube, which distal length is formed with a contact end projectable from said outlet mouth for wiping transfer of fluid 4 to a worksurface therefrom, the pen also being formed with longitudinal channel means between the inner circumference of the outlet tube and the distal length of the rod which is embraced thereby, thus to enable flow of fluid from the reservoir to the contact end,

a length of said cylindrical rod which traverses said smooth bore length of the tubular body having radially extending rib means disposed slidably longitudinally along the bore, and the exterior of said smooth bore length having handle attachment means for disposing an operating handle extending transversely therefrom, whereby the intersection of said rod with a plane extended through said handle attachment means and said rib means locates a fulcrum below which vibration of the rod within the outlet tube caused by writing, promotes descent of fluid along said longitudinal channel means to the contact end of the rod and thence to a worksurface.

2. The Writing pen of the preceding claim 1 wherein said rod is threadedly engaged with the tubular body proximate to said rib means, thus constituting said positioning means, and said rod carries a valve member serving as a closure for said reservoir upon seating across the tubular body upon threaded axial displacement of the rod.

3. The writing pen of the preceding claim 1 wherein said longitudinal channel means comprise spiral flutings formed along said distal length of the rod, and said contact and thereof is dome-shaped.

4. The writing pen of the preceding claim 1 which additionally includes pen support means comprising an inverted thimble and an outwardly extending footing member centrally supporting the thimble upstanding therefrom, said thimble being formed with an encircling band intermediate its height which is adapted to outwardly and loosely embrace said tubular body so that the dependently projecting contact end of said rod hangs free within the thimble, the latter also being formed with an open-top slot adapted to receive a transverse shaft of said handle attachment means when the tubular body is seated within said encircling band.

5. The writing pen of the preceding claim 1 wherein said handle attachment means includes an attachment shank having one end thereof secured transversely to said tubular body external to said rib means, and having a handle extending outward from the other end of said shank,

pen support means comprising an upstanding inverted thimble formed with encircling bands of successive upwardly-increased diameter whereby a portion of said tubular body adjacent said attachment shank may be outwardly and loosely embraced by one of said bands with the dependently projecting contact end of the cylindrical rod hanging free therebeneath within the thimble, said thimble being formed with an upward-directed, open-top slot adapted to receive said attachment shank disposed transversely thereto upon vertical insertion and removal of the pen from the thimble,

and a generally horizontally disposed, ring-shaped footing member formed with a generally centrally-directed arm and a generally axially upstanding stud arising from said arm and supportingly engaging the lower end of said thimble.

References Cited by the Examiner UNITED STATES PATENTS 1,340,926 5/1920 Weitz 12045.6 X 1,528,142 3/1925 Bourquin l2044 1,824,275 9/1931 Kellog l2044 2,855,897 10/1958 Benkowski l2044 2,982,252 5/1961 Benkowski 12042.6

LAWRENCE CHARLES, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,286,695 November 22, 1966 Jack M. Martin It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 4, lines 29 and 30, for "contact and" read contact end Signed and sealed this 12th day of September 1967.

(SEAL) Anew ERNEST W. SWIDER Attesting Officer EDWARD J. BRENNER Commissioner of Patents 

1. A HEAVY-FLUID WRITING PEN OF THE CHARACTER DESCRIBED, COMPRISING: A TUBULAR BODY FORMING A FLUID RESERVOIR, AND A DEPENDENT OUTLET TUBE DISPOSED FOR GRAVITATIONAL PASSAGE OF VISCOUS WRITING-FLUID FROM THE RESERVOIR LENGTHWISE THROUGH SAID TUBE TO AN OUTLET MOUTH, SAID BODY ABOVE THE OUTLET TUBE BEING FORMED WITH A LENGTH CHARACTERIZED BY A SMOOTH BORE AND GREATER INTERNAL DIAMETER THAN THE OUTLET TUBE, A GENERALLY CYLINDRICAL ROD DISPOSED AXIALLY MOVABLE WITHIN SAID BODY AND HAVING POSITIONING MEANS FOR SELECTIVELY LOCATING IT THEREALONG WITH A DISTAL LENGTH OF THE ROD CLOSELY EMBRACED BY SAID OUTLET TUBE, WHICH DISTAL LENGTH IS FORMED WITH A CONTACT END PROJECTABLE FROM SAID OUTLET MOUTH OF WIPING TRANSFER OF FLUID TO A WORKSURFACE, THEREFROM, THE PEN ALSO BEING FORMED WITH LONGITUDINAL CHANNEL MEANS BETWEEN THE INNER CIRCUMFERENCE OF THE OUTLET TUBE AND THE DISTAL LENGTH OF THE ROD WHICH IS EMBRACED THEREBY, THUS TO ENABLE FLOW OF FLUID FROM THE RESERVOIR TO THE CONTACT END, A LENGTH OF SAID CYLINDRICAL ROD WHICH TRANSVERSE SAID SMOOTH BORE LENGTH OF THE TUBULAR BODY HAVING RADIALLY EXTENDING RIB MEANS DISPOSED SLIDABLY LONGITUDINALLY ALONG THE BORE, AND THE EXTERIOR OF SAID SMOOTH BORE LENGTH HAVING HANDLE ATTACHMENT MEANS FOR DISPOSING AN OPERATING HANDLE EXTENDING TRANSVERSELY THEREFROM, WHEREBY THE INTERSECTION OF SAID ROD WITH A PLANE EXTENDED THROUGH SAID HANDLE ATTACHMENT MEANS AND SAID RIB MEANS LOCATES A FULCRUM BELOW WHICH VIBRATION OF THE ROD WITHIN OF OUTLET TUBE CAUSED BY WRITING, PROMOTES DESCENT OF FLUID ALONG SAID LONGITUDINAL CHANNEL MEANS TO THE CONTACT END OF THE ROD AND THENCE TO A WORKSURFACE. 